Topic: E-devices suitable for backup storage of seed phrases. (Read 458 times)

Trusting your memory for important data like seed phrases shouldn't be done. You should have physical backups of the entire phrase, not just a bigger or smaller part of it. I know this discussion is about digital backups, but I am just saying. And even if someone found your seed backup that contains 8 out of 12 words, the remaining ones can be bruteforced.

Have you checked to see what kind of flash memory all these devices are using for their operation?

If it is a NAND flash then you have a security problem there, as the device can be disassembled and the memory extracted in order to try to use more advanced (magnetic?) methods to recover the mnemonic from the memory - even after it is wiped.

If it is of the volatile kind then you need to somehow ensure that the data really is zeroed out by losing electricity after a power off.

How about making a tails OS USB, encrypt it and store your seed phrases in that USB. In most cases, if anyone get hold of that usb he will format it, because when the tails OS enabled usb is attached to the Windows OS computer, it will shows someting like wrongly formatted ad the person who get that USB will format it to use it. ( there are very few who know about tails OS and even fewer who can think the usd contains seed phrases.

Another thing can be to have your extended seed phrase, where the last four words of the seed phrase to remain in your memory so even if someone hacks into the USB, he or she will still not be able to open your wallet.

Here is the details on How to Install Tails OS on USB flash drive for Wallet Purpose, you can install the air gapped wallet directly too on the USB.

I found another alternative for G-Shock G-2900 watch.
This is another model from Casio and it has the same features and memory with slightly different design and dimensions.
It is using different module 2957 and watch model is G-Shock G-7600



Here is short video and comparison with G-2900:
https://youtu.be/ifDyyceFDlk

So does your regular writing of seed words on paper, there is no encryption there and no password.  
Nobody should used this devices for long term storage of bitcoin llfe savings.

No they don't.
This are not devices designed to protect against brute force attacks, same as paper backup.
You can use Satochip cards for that because they are encrypted.

Most devices mentioned here are dumb and offline dude.

In the code of a 20-year-old calculator (when the founder didn’t even have thoughts about creating bitcoin) without the ability to connect to the Internet, malicious programs could certainly be hidden.
/sarcasm off


What kind of encryption can there be on devices that are not designed to store seed phrases? Let's start with this.

In the devices discussed in this topic, another method of protection is discussed - to hide the seed phrase on a device where no one expects it (masking).

Thank you for your invaluable comments on a thread where no one reads the introduction.

None of the options on this thread include ENCRYPTION.

Only password protection.... shoddy at best for keeping something as valuable as cryptocurrency private keys secured.

Physical > Encryption > Plain text private keys

YOU NEED LAYERS OF PROTECTION ON THE PHSYICAL DEVICE TO PREVENT A BRUTE FORCE ATTACK.

Using networked devices for this task is a bad idea. Use offline methods.

I am not a fan of any digital ways of storing seed phrases and private keys, but if for some reason it has to be done, it's good to know there are some options. I would prioritize a device capable of encrypting the data in its memory and, obviously, there can't be any internet, Bluetooth or other ways to transform data from it. Being open-source isn't that important of a factor if there is no way to connect to the internet with it. And even if it is open-source, I doubt security experts were or will be standing in line in the future to investigate the code of 20 year old Casino calculator or a similar gadget.

There are some of them with removable batteries, Fairphone is first thing that pops in my mind, it's open source, and they are even giving away free additional battery with every purchase of Fairphone 4 and Fairphone 5 models.
I heard about other alternatives but I don't know how active they are, and there are still cheap dumb phones available in most places.

Another phone that is popular with minimalist people who don't like smartphones is CAT S22:

Theoretically, this is possible, but practically, being paranoid, I would think about this solution 10 times.

The fact is that the main function of a SIM card is subscriber authentication in the cellular network. That is, even without a SIM card, the phone can work (with some reservations), for example, calls to emergency numbers, like 911 (which are most often built into the GSM standard).

And I can find it completely free in a box of old mobile phones in my closet.

This is undoubtedly an advantage, as is the ability to add a password to access phone data.


Old phones, unlike new Chinese push-button phones, don't have built-in backdoors and dubious apps that send data to their servers, therefore, it is better to use older mobile phones.

The text can be saved anywhere, from a notebook, a calendar, to a contact list. Limitations depend only on imagination.

I assume you're concerned about battery life, I used nokia that can lasts for days even with intermittent usage but he all it needs standby or even turning off and on won't be a problem which makes it highly reliable option in my perspective. I don't know the new era keypad mobiles are coming with removable batteries, if they do then I don't see any problem with them.

This seems to be a good idea if you ask me, the old ones do not have any internet connections and only come to live as when a SIM card is inserted, they can be used for the purpose as you can save messages as text on drafts. They are definitely below the $40 price. My only problem is you cannot switch them off for a very long time as they usually run into ba3 problem but it’s a good option.

Advantage of using a watch is that you can easily have it on your wrist, and almost nobody would suspect what you have hidden inside it.
I have been trying to find other wristwatches that could be work in similar way, without being a smart watch, but no luck so far.
Maybe that is not a bad thing, there are plenty of G2900 available in Japan and worldwide.

As far as I know there are no more G-shock models in production that have Data Memory.
There are other models but they have smaller memory compared to G-2900.
You can check them all here:
https://shockbase.org/function_page_dyn.php?function=data_memory

There are several Casio Databank models but I am not sure how big their memory is:
https://en.wikipedia.org/wiki/Casio_Databank
https://www.casio.com/us/watches/casio/databank/

They use cheap CR2025 battery that lasts for years with no problem, but when removed it's all gone, that could be a good thing also
Casio gave it 10 year rating, but people say it lasts longer if you don't play with watch and light all the time.

How about an old keypad mobile or even a new one without inserting sim cards be considered for this purpose?

I can find some keypad mobiles that are brand new and available for under $50 - and  $40 can do the job.

Availability is everywhere, we do not need to worry about the data stored getting deleted like calc and data dictionaries.

It was your mention of G-shock that prompted me to think about this method of storing seed phrases.


The concept of large or small quantities of coins is different for everyone, but one can argue that such methods of storing cryptocurrencies should not be used as the main and long-term one.

Curious, does Casio (or another) produce watches with memory cells now? Smart watches are not considered

This watch model (e-DATA memory) can store up to 40 records.

"of 7 characters each, or more or less records depending on the number of characters used for each record"

source: https://www.g-central.com/specs/g-shock-g-2900/

What memory does this watch use? Autonomous? If the battery is removed, discharged (as the manufacturer assured, the battery life is 10 years ) or is damaged due to physical impacts, then the internal memory data will probably disappear forever.

Of course, this watch looks like one of the best solutions as an e-device for storage of seed phrases, because it is always at hand.

Yes, I also like this idea, but with some modernization (for an amateur): HW watch should look something like a G-shock, which normally works like a watch, but as a “second bottom” it is used as a hardware wallet (connecting to a PC via USB). Although, tailoring the hardware wallet to a smartwatch also looks good (I'm sure this product could be more widespread). It seems to me that generating a QR code and displaying such at watch on the display to confirm a transaction (for example, scaning it from a smartphone camera) would be a good solution.

I found one old Casio G-shock watch that could work very good as device for storing seed words, but this should not be used for storing large amount of coins.
Exact model of watch is G-Shock G-2900, it was released back in year 2002 and it not manufactured anymore, but it can be purchased as used device.
G-2900 have one of the largest data memory from dumb casio watches, and this can be used as offline storage for keys and any other text, with additional password protection.
This watch is perfect for traveling, it is very durable, hard to destroy, and it won't bring much attention from anyone.

There was also one hardware wallet BITHD Watch 2 that looked more like modern smart watches, but it is not produced anymore and Bithd website is down.
It would be interesting to have more hardware wallets in form of wrist watches.

 

If you travel a lot, you already probably know that some customs are racists, moody and love when they mess with you. If you are EU citizen and travel inside EU, everything goes smoothly but outside of EU, it's a little bit headache to my mind. I personally wouldn't risk traveling with such a device in Australia, their customs are one of the strictest ones.

Don't get me wrong, I would love to discuss within the framework of your concept but I don't understand the pros of your idea and I'm trying to find one. I am sure it's never a good idea to bring additional electronics in airport if you want to safely pass the check. To be honest, I love the idea of Smart Watch and MP3 player, it's very creative to write tracks on your MP3 player and name them like seed phrases.

I have used this type of calculator in my high school days. I could remember while so many others were using it for mere arithmetic, I and my friends were using it to save data such as mathematical formulas. This gave us some undue advantage over them. Using it to transport seed phrase is a thoughtful idea, but the simplicity of the process is in doubt.

This brings me to what synchronice said
Even if not within the scope of this discussion, using paper to pen down the seed phrase with an airgaped device for travel purposes is not a bad option.

The lack of encryption means that if a friend next door or at the airport notices it, will try to read it. Humans love to snoop and read other people's diaries, and the old design may attract attention.

Some of these devices contain a USB port, which is sufficient to transfer data, especially since the programming of these devices is old and we are talking about unencrypted text content.

I think that some old multifunctional calculator is capable of storing 12 words without USB port and burned code, with the ability to hide them easily. it will be Best option

I see. Anyway while i find￡43 is cheap for such new device, that amount of money also enough for few hardware wallet (such as Blockstream Jade which cost $40).


At least for custom officer on some country, vague "reasonable suspicion" and random inspection are fairly common reason to go through all your devices.

Corrected the link.

At that time (when I saw this device), the price was not displayed due to the fact that all devices were sold out. Probably the seller has a new supply of goods and therefore he has put up a price tag.
The price may vary due to discounts and is currently ~￡43 (about 2 times less than what you specified).


Determining the degree of suspicion is a very subjective thing.

And not in the hands of a young man, but in a backpack (baggage). There is no need to demonstrate such gadgets publicly unless you have an electronic notebook and a calculator in your smartphone.

And when crossing customs officers or a police search, what business is it of theirs what a person is interested in (old gadgets), if it doesn't violate any laws.

You have the right to do as you think is right. I would prefer to discuss within the framework of the concept that I described.